Photographic emulsions sensitized with n, n-alkylenecyanine dyes



Feb. 8, 1949. G s, BROQKER 2,461,137

PHOTOGRAHI EMULsIoNs SENSITLZED WITHv N, N-ALKYLENECYANINE DYEs Filed Sept. 4, 1946 FIG.1.

III Vm 1111 |1|11I11 11| \1|1| 111i FIGZ.

AVA

FIG. 3.

LESLIE G. S. BROOKER I BY NVENTOR 'atened Feb. '8, 15949 UNITED STATES PATENT OFFICE Pno'roGRAPHI'o'EMULsIoNs sENsrrizEri v WITH N,NALKYLENECYAIE DYES Leslie G. S. Erooker, Rochester, N. Y., assignorxto Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Application September 4, 1946, Serial No. 694,837

6 Claims.

Contrasted with these known N,N'alkylene cyanine dyes which are always monomethine dyes, my new dyescontain an alkylene group attached to each of the nitrogen atoms of two heterocyclic nuclei which are notlinked together through their alpha positions. My new dyes can be monomethine Aor polymethine and I have called them N,Nalkylene cyanine dyes to contrast with the known N,Nalkylene cyanine dyes. My new dyes are polymeric in nature and have at least two molecules (or units) of a cyanine dye salt linked together through a heterocyclic nitrogen atom terminal to the conjugated chain of atoms of each by a-hydrocarbon radical, the terminal nitrogen atoms being attached to a carbon atom of said hydrocarbonV radical which may be aliphatic or cycloaliphatic. An example of one of my new The formula of this dye can also b e drawn show ing the two iodideanions' attached to the nitrogen atoms to which the ethylene group is attached or showingthe two iodide anions yattached to the nitrogen atoms of the twobenvzoxazole'l nuclei. For convenience of graphicalrepresentation; the formulas used hereafterwill be drawn to show the anions attached-to the left-hand nuclei, i. e. the benzoxazole nuclei in the above example.

It is, accordinglyfan object of my invention to provide new dyes.V Another object is toprovide a process for preparing such dyes. A still further objecti is to provide photographic lemulsions sensitized with such dyes. Other objects will appear hereinafter, l Y

The rst group of new dyes of my invention can be represented by the following general formula: Y

wherein d, efand n eachv represents a positive integer-of fronione t0 two, D represents an al,n kylene group,L represents a methine group,v Q

represents the :1on1-metallic,V atomsnecessary to complete a heterocyclic nucleus containing from 5 to 6 atoms in the heterocyclic ring, R represents a member selected from the group consisting 0f alkyl and aryl groups, X represents an anion and Z represents the non-metallic atoms necessary to complete a heterocyclic nucleus containing from 5to 6 atoms in the heteroc'yclic ring.

More particularly in the'above general formula D represents an alkylene group, e. g. a bivalent hydrocarbonradical, for instance ethylene, tri: methylene, hexamethylene, 1,4-cyclohexylene, decamethylenefr etc., =`L represents ,-CII=, C(CH3)=, etc., Q represents"thenonmetallic atoms necessary to complete a nucleus of the thiazole series, e. g; `4methylthiazole, 4-phenylthiazole, 4,5-diphenylthiazole, 4-.(2thienyl)thia zole, etc., a nucleus of the benzothiazole series, e. g. benzothiazole, 5-chlorobenzothiazole, 6- chlorobenzothiazole, 5-dimethylaminobenzothia- Y zole, B-methoxybenzothi-azole, G-methylbenzoetc., a nucleus of the selenazole series, e. g. selenazole, 4-methylselenazole, 4-phenylselenazo1e, etc, a nucleus of the benzoselenazole series, e. g. benzoselenazole, 5-chlorobenzoselenazole, etc., a nucleus of the benzoxazole series,` e. g. benzoxazole, 5chlorobenzoxazole, 5-methoxybenzoxazole, 5-phenylbenzoxaZele', etc., a nucleus' of the 3,3- dialkylindolenine series, e. g. 3,3dimethylindo lenine, etc., a nucleus of the Quinoline series, e. Vg. n quinoline, G-methylquinoline, G-methoXyQuinolI line, -chloroquinoline, etc., R- represents-an alkyl group, i. e. an alcohol radical, e, g; methyl; ethyl; n-propyl, n-butyl, isobutyl, allyL-ethoxyethyl,

ylethyl, -acetoxyethyl, etc., or an aryl group,v such as phenyl, X represents an anion, e. g. chlo'- ride, bromide, iodide, ptcluen'esI zlf'ona'te,YY bene.L zenesulfonate, acetate, perchlorate, thiocyanate,` etc., and Z represents vthe non-metallic z'itorrrs'` necessary to complete 'a nucleus of the thiazole series,"e; g.A imethylthiaoleg i-phenyltlfii'azcle, 4,5diphenylthiazol'e, 4*-(2i-thienylyth'iaz'ole, etc., l'a'nucleous of the benothia'zole series, e. g1; 'benzin 4thiazole, 5'chloroben'zothiazole, 6chlo`robehzo thi'azola 5-dimethyla-minobenzothiazole, 6'-`m'eth ylbenzothiazole,V ebromobenzothiazole, 4rneth oxybenzothiazole, "I-chlorobenzotl'iiazole, etc., `a nucleus of the naphthothiazole series, e. lg. anaphthothiazole, enaphthotl'ia'zole, etc., a nucleus ofthe-selenazole series, e; 'gx selenazole, 4- I'n'ethylselenazole, 4"-phenylselen'azole, etc., a nu'- cleus of the benzos'elenazole series, e; g. benzoselnazole, --'chlorobenzoselenazole, etc., a3 nucleusgof the benzoxazole series, e; ig. benzoXazole, 5- 'r chlorob'enzoxazole, 5-methoxybenzoxazole; 5- phenylbenzoxazole, etc., a nucleusofthe '3B-difalkylindolenine series, e. g. 3,3-dimethylinb'- lenine, etc., a nucleus of the Quinoline series, e. g.

Quinoline, 6-methylQuinoline; 6methoxyquino In accordance with my invention, I provide the dyes represented by formula I above wherein e represents 1 by condensing a cyclammonium Quaternary salt containingin the e or 'y1-positions, i. e. oneofthe so-called reactive-positions, a member selected from the group consisting of 'halogen atoms of` atomicweight' greater thanf35 yandlthioetlier groups, i. e. a cyclammoniumfquaitf ernary salt selected from those represented by wherein` n, Q. 'R' and X have lthe valuesV 'given above and. X1 representsfa member selected vfrom the.A group consistiiigof 'a haloge'natom offaioniic Weight greater than 35` and a tliioefther group; with abis cyclammo'nium Quaternary Vsalt select;- 'edffrom those whichV are'repres'en'ted byftle "fol-V lowing general frmula:

above, andRzvrepresents.-a'fliydrogenfatomorren. alkyl group'. The .preparation of these. 'bis- T651;

fer

Yzaln mei-.hn-pltoluenesulfcnate etc.

thia'Zole Veth0'--petoluenesulfonate, 2-methylmeroaptobenzoxazole metho-p-tolunesulfonate, 4- phenylmercaptopyridine ethiodide, 4-phenylmerbaptoquinoline ethiodide, Z-methylmercapto-- naphthothiazole metho-p-toluenesulfonate, 2- methylmerca-pto-naphthoxazole, metho-.pitbluenesulfcnate; letc..`Y Y Y 'The condensa-tions 'are fadvzmtageouslyfcawied o'utin the presence of a.basicfcendensingiaaent (acid finding-agent); e. e. -a tertiayfamine, especiall'y-"a tertiarya e havirigfI/anionizatimxzc'cin'- sta-nt: greaterthan 10i-'5 at25f'"C, e..1g.lt1fa'lkyl amines' rtriiseamylamine; triethylamine;Y 'tri-na. prepylaini-ie; ltrfi-ne-butylarnineetc); fi'f'liih'ydmay;-

. ainda-mines (triethanelarnine rriprnpanoiamine,

etc), N-alkylpip'eridiines (Nrmethyilpipenidinef, Ni ethylpiperidine, etc.) and so forth; Alkali metal carbenates, e: g. so'ain'm anu potassium Gerben,- ates, are eilcacious basic condensingzagents'; The condensations are advantageously carried out in a solvent, especially an alcoliche. g ,ethyl, n-propyl or n-butyl'alcohol, i. e. anv alcohol'of the for.. mula CnHzeH'OH whereinnfrepresents a positive .integer offrom 1 to 4.-. Pyr'idine-.is .likewise an efcacious solvent.

To preparerdyessofz-the above general formula I wherein e represents one, I can also condense a cycla'mnnimiumA Quaternary ysalt"contairringifin'the af. or 'v-.pcsitiimfan allgvligrcup, i; eg a cyclammo: -niumi Quatemiary saltA selected; from: those;repre. sented by: the followinggeneral fnnmulatf wherein; d; VL,Y Q; Ri'and Xhavefthei yaluesfgiven above and R3 represents: arlhydro'gematomssonarn alkyl greumfwithe'a -bis'falkylmercaptnnyclammo; nium Quaternaryfsalt.lselectedrvfncm ttiosexrleprel sented by :the: following :generalformula:.2v

Wherein'D, L,- n, X and Z representthevalus given above and R4 represents an alkyl group. Typical of thef'quaternary salts represented by formula IV are: Quinaldine ethiodide, lepidine n-butodide, 2-methylbenzothiazole metho-ptoluenesulfonate, 2-n1ethylbenzoxazole eth'rodide, 2-methyl'llhphenylthiazole. ethiodide, 2-metlylthiazoline methiodide, '2methylmaphthotliia Y The preparation of the bis alkylmercapto cyclammonium Quaternary salts is described herein-after. The

condensations are advantageously carried out in the presence of a basic condensing agent and solvent of the character of those described above.

To prepare dyes of the above general formula I -wherein e represents two, I condense a cyclamy monium Quaternary salt containing in the aor v-position a -arylaminovinyl group, i. e. a cyclammonium Quaternary salt selected from those represented by the following general formula:

R Re

wherein n, Q, R and X have the values given above, and R5 represents an aryl group, e. g. phenyl, p-chlorophenyl, p-tolyl or -naphthyl and Re represents a hydrogen atom, an alkyl group, e. g. methyl, ethyl, etc. or an acyl group, e. g. acetyl, propionyl, butyryl, etc. with a bis cyclammonium Quaternary salt selected from those represented by formula III above.

Typical of the quaternary salts set forth by formula VI are: Z--acctanilidovinylbenzoxazole ethiodide, 2-acetanilidovinylbenzothiazole ethiodide, 2--acetanilidovinylquinoline ethiodide, 4-acetanilidovinylquinoline n-butiodide, 2-,3- acetanilidovinyl--naphthothiazole ethiodide, 2- -anilinovinylthiazoline methiodide, 2 -acetanilidovinylbenzothiazole pheniodide, 2-acetani lidovinylbenzoselenazole ethiodide, 2-/i-acetanilidovinyl-4-methylthiazole methiodide, 2--acetanilidovinyl-4-phenylthiazole ethiodide, Z--acetanilidovinyl 3,3 dimethylindolenine methiodide, 2- [2- (N-methylanilino) vinyl] benzothiazole ethiodide, 2- (-acetanilidovinyl) -3,4trimethyl enebenzothiazolium iodide, etc.

The condensations to produce the bis trimethine dyes are advantageously carried out in the presence of a basic condensing agent (acid-binding agent), e. g. a tertiary amine, especially a tertiary amine having an ionization constant greater than -5 at 25 C. e. g. trialkylamines (triisoarnylamine, triethylamine, tri-n-propylamine, tri-n-butylamine, etc.) trihydroxyalkylamines (triethanolamine, tripropanolamine, etc), N-alkylpiperidines (N-methylpiperidine, N-ethylpiperidine, etc.) and so forth. The condensations are advantageously carried out in a solvent, especially an alcohol, e. g. ethyl, n-propyl or n-butyl alcohol, i. e. an alcohol of the formula CnI-Izn-HOH wherein n represents a positive integer of from 1 to 4. Pyridine is likewise an eflicacious solvent and in some cases suffices as basic condensing agent.

To prepare dyes of the above general formula I wherein e represents two; I also condense a cyclammonium Quaternary salt containing in the zor y-fposition, a ,B-alkylmercaptoalkeny1 group, i. e. a cyclammonium quaternary salt selected from those represented by the following general formula:

VII

wherein L, n, Q, R and X have the values given above and R7 represents an alkyl group, e.'g. methyl, ethyl, n-butyl, etc. with a bis cyclammonium quaternary salt selected from those represented by formula III above.

Typical of the Quaternary salts set forth by formula VII are: 2-(Z-methylmercapto-l-butenyD-benzothiazole metho-p-toluenesulfonate, 2-

give bis trimethne cyanine dyes are advantage- (Z-methylmercaptopropenyl),- naphthothiazole metho-p-toluenesulfonate, 2-(2-methylmercaptopropenyl)3,4-trimethylenebenzothiazolium p toluenesulfonate, 2-(2methy1mercaptopropenyl) benzothiazole ethoptoluenesulfonate, 2-(2- methylmercapto-1-butenyl) benzothiazole -phenop-toluenesulfonate, Y5 chloro-2-(2-methylmer- -capto-l-butenyl) benzoselenazole metho-p-toluenesulfonate, 2- (Z-methylmercaptostyryl) benzothiazole ethiodide, 2-(Z-methylmercaptostyryl) -naphthothiazole ethiodide, 5chloro2v(2meth ylmercaptopropenyl) benzothiazole ethiodide,V 2- (2-methylmercaptopropenyl)quinoline eth0-p` toluenesulfonate, 2-(2-methylmercapto-1-butenyDquinoline metho-p-toluenesulfonate, 2-(2- methylmercaptopropenyl) -4-phenylthiazole ethop-toluenesulfonate, 2- 1methy12methy1mer capto-l-butenyl)benzothiazole metho-p-toluene.- sulfonate, 2-(-cyclopropyl--methylmercaptovinyD-benzothiazole metho-p-toluenesulfonate, Z-(-cyclopropyl methylmercaptovinyD-- naphthothiazole metho-p-toluenesulfonate, 5- chloro-2- (-cyclopropyl--methylmercaptovinyl) benzothiazole metho-p-toluenesulfonate, 2- (-cyclopropyl -methylmercaptovinyl) -benzoselenazole metho-p-toluenesulfonate, 2-(-cyc1obutyl- -methylmercaptovinyl)benzothiazole metho-ptoluenesulfonate, 2-(-cycloheXyl--methylmercaptovinyDbenzothiazole metho-p-toluenesulfon ate, 3 ,3dimethyl2 (-methylmercaptovinyl) indolenine methomethylsulfate, etc. Many of the -alkylmercaptoalkenyl compounds are known substances. Others are described in the cepending applicationsof GraftonI-l. Keyes, Serial No. 597,149, lecl June 1, 1945 (now U. S. Patent 2,429,469, issued October 21, 1947); 620,161, filed October 3, 1945 and 620,162, led October 3, 1945.

The condensations (involving the 2-a1kylmercaptoalkenyl cyclammonium Quaternaryy salts) to ously` carried out in the presence of a basic condensing agent and solvent, e. g. the basic` condensing agents and solvents set forth above under the condensations involving the -arylaminovinyl cyclamrnonium quaternary salts.

The following examples will serve to illustrate further my new dyes and the manner of obtaining them.

, 02H5 I S alcohol layer was decanted and the'resid-ue was @timed with mater. me y.seiici was iaelieoied :on estimer., ineens)fermed ;to a test tube, stirred with mental-ter two'recry-,itellizations f-Vromimethyl also l1:1401. The brick red pmi/der Seftened @om :19.2 and .deomposed ai 202i' C., .and it Aeensitizeri -photqeraphgelatineesilyeibromioldideemuisn to .about 550 mu maximum lsensitvi-ty et @bout 512.0 mn- .thiaeQlOeZ-ecyenifte iodide) time mixture, the Adye .separated as a Stickymass. y,

flhe sticky mass Was tturated rt with @filler then with acetone- Thedye was filteredfrein 5121.12 qcetQiie, Was/hed with water anllried. [After `ref;iystfillzation .irQmmethylemdmL ,ihedye was qlgtgined in 6 per c ent yield ,as ln 'imi'telo`1ao-wgx qrfystells hay/ing a g1-een reex .and melting at2-92 1:9293" C. Wtih decornpositiolifi;- The dye v`.gerilusitized a photographic gelatinoesilverebroigiodicle emulsion .to ebeut z57.0 ,me Awith maneum eeesitivty at about 530 mit.

einigem@ an be condensed with s'rmephyleee bis(2-methylmercaptobenzothiazolium p etgllieglef sulfonate) to give 3,3methy1ene bis(3ethyl thiewenine iodide), 0r 2 vmethylbeezeetele ethiodide can be `condense.d gil- 1th the bis salt t0 give 3,3'methylene bis(3-ethylggathiacyanine iodide) rielieium iodide) -eine lone. of enhy1a1coho1,

191g. (74413719115.) ,of triethylamiine yvaswaddedto -,QG ,e4 mele.) ef Zfifiequieoline ethioeide 1,35 g. (1 mei.) of ,3,3rzriniethy1enebis A 2- methylbenzothiazqlum brmige) and l10 cc. of ethyl elQliQL gndfthe -reaction mixture Ewas ,ljleted Yaijltx'le viev'iuiiri;'g temperature foei 15 unliites, After chillngeit 0 .the dye was Q91.- egted e, lter @nel weighed with 'rglethyl valchol unid tigen gelabelt. The yeldf `dye -Was 'i5 percent cigjicleen .per t serit, in two erops, after @ne re- Qigy segel-liz@tion Yfrom methyl -alchol lThe red ,criletalsliad .a melting paint of 304130 C, .with

out. The dye was washed with Water and purified by recrystallization from methyl alcohol. It was obtained in 4 per cent yield as a dark red crystalline powder melting at 288-289" C. with decomposition. The dye sensitized a photographic gelatine-silver-bromoiodide emulsion to about 610 my. with maximum sensitivity at about 560 ma.

Example 6. 3',3 ethylene bis (3 ethyl 4"- methyloxarhiazolo-carbocyanine iodide) 0.81 g. (1 mol.) of 3,3ethy1ene bis (2,4-dimethylthiazolium chloride), 2.17 g. (2 mols.) of 2-,8-acetanilidovinyl-benzoxazole ethiodide, 10 cc. of absolute ethyl alcohol and 0.5 g. (2 mois.) of triethylamine were refluxed for 20 minutes. Upon chilling, the dye separated and was ltered off, washed with Water, and purified by tWo.recrystallizations from methyl alcohol (250 cc. per gram of dye). It was obtained in 9 per cent yield as a red powder, melting at 208 to 211 C. with decomposition. The dye sensitized `a photographic gelatino-silver-bromiodide emulsion. to about 590 me with maximum sensitivity at about 550 my.. I

Example 7.3',3'ethyzene bis (s cmoro-s-ethyz- 4'-phanyZthiathiazolocarbocyanine iodide) Themixture of dyes, which weighed 0.75 g., was vextracted with two portions of hot methyl aloof zholggicc. and 350 cc. respectively. lFrom the- 350jcc. fraction there was obtained 0.28 g.v of dye.

10 After another recrystallization, the yield of dye was 10 per cent. The dark green crystals had a. melting point of 292-293 C. with decomposition, and they sensitized a photographic gelatinosilver-bromoiodide emulsion to about 650 mp. With maximum sensitivity at about 615 me.

In like manner, 3,3'ethylene bis (B-ethyl-ifphenyl 4,5 benzothiathiazolocarbocyanine iodide) was prepared by using.2.5 g. (2 mols.) of 2- acetanilidovinyl--naphthothiazole ethiodide in place of 2acetanilidovinyl5chlorobenzothiazole ethiodide. The yield of dye was 6 per cent after the first series of extractions and 4 per cent after two more recrystallizations from methyl alcohol. The minute green crystals had a melting point of 254-255 C. with decompositien, and they sensitized a photographic gelatinesilver-bromoiodide emulsion to about 690 ma with' maxima sensitivity at about 580 mp and 630 me.

In like manner, 3,3-ethylene bis (1'-nbutyl4 phenylthiazolo-4carbocyanine perchlorate) was prepared by using 1.57 g. (2 mols.) of 4ace tanilidovinyl quinoline n-butiodide in place of 2- acetanilidovinyl--chlorobenzothiazolev ethiodicie, and then converting the dye to its perchlorate. The yield of dye was 2 per cent. The dull purplish powder sensitizedv a photographic gelatino-silverbromoiodide emulsion from about 6,50 mp. to about '700 me with maximum sensitivity at about 680 me. n y

In like manner, 3',3'ethylene bis (3-ethyl-4- phenylthiathiazolocarbocyanine iodide) was obtained in a yield of 3 per cent. The minute greenish crystals had a melting point of 298-299 C. with decomposition, and they sensitized a photographic gelatino-silver-bromoiodide emulsion to about 660 ma with maximum sensitivity at about 620 me.

Example 8.-3',3'ethylene bis (3-ethyl-5-meth- 1l-4'-phenyloxathiaeolocarbocyanine iodide) C 2HE 0.25 g.. (2 mois.) of triethylam'ine was added to l1.12 g. (2 mols.)l of 2'acetanilidovinyl5methylbenzoxazole ethiodide, 0.56 g. (1 mol.) of 3,3- ethylene bis l(2-methyl-4-phenylthiazolium chloride) and 10 cc. oiv absolute ethyl alcohol, and the reaction mixture was .heated at the refluxing temperature for 20 minutes." After chilling at 0 C., the dye was collected on a lter and AWashed with acetone, then Water and finally more acetone. The yield of dye was 18 per cent crudeand 10 per cent after two l recrystallizations from methyl alcohol. The small crystals had a melting point of 261-262 C. with decomposition, and they sensitized a photographic gelatine-silver'- imum sensitivity at about 570 mp.

mesma# sitized-azphotographic gelati-ino-silvewbromoiodide emulsion -12o-about 611')VV mi with-maximum fsensi'- tivityett aibout 'llimfi.

Eli-ampie;1areasemmemyiene..bis -cs-emgzem thiaca'rbocyanine iodide.)

0.5 g. 2 mois.) of triethylaminefxvas added to 2.17 g. (2 mals.) of Z--acetanilidovinylbenz- Qxazole ethiodle, 1.25 g. (1 mol.) of 3,3tr1 methylene :bis ('ZLmethylberIznthiazolium bromide) andlll' cc. .of ethyl alcohol, andthe reaction vmixture was heated. .et the reuxing'temperature or 10 minutes. After ChillingY at. 0" CL, forLtWo days, with some stirring, the solid kwes. collected on 'a iil'ter. beeiker and stirred withwater.. The cl5fe`*il:a;s-.col-E lected on '9. 'filter andthe lnely divided solid was Washed'witli Water. Tl'reyieldm dyewas 43 Apei` cent. after two .recrystellizations from methyi alcohol CIS() cc. per gram of dye). The minute reddish cliystals softened at"222 C. and Vdecomgraphic'. ngeltimeisili/'elf-Frosiidimilde emulsion Vto 'Hiesticky r'esidile Wals "transferred to a about 590' me' with maximum sensitivity at "about 555 my.. Y

'TrlA like manner, 3,3et1imethylerxe bis(1'n' 'biityltiia-"-cali'bocymaine iodide) `was pre'pei'ed by'lemployingfi g. "(-2 mols.) of 4;l'acetanilido vinyl 4du'in'olin'e n-ibiitiodide in place of I2-f5 ecetaniiidovinylbeuzoxazole ethiodide. The yield ofdyewas 2713er cent after two recrysteilizetions from methyl dl'eoliol (280 cc. per gram-of dye). The dark blue crystals had a. melting' point of 2082l0 C. with. decomposition, and they sensisized .ayhotogrphic geletino-silver-bromoiodide emulsion from 'about 600 me to about 690 my. with maximum sensitivity at about 660 me.

Example. 1i-l .-333 -trimethy'lene bis (S-ethyl-4 phenylomat'hiazolo-carbocyanine iodide) LLB-1g. (42 mois.) of triethylamine was. added 'to 258 g. (1.2 molsf) of IZ--acetanilidovinylbenz- .oxazzolev.ethiedde,.1.7;g.'(l mol.) of 3,3-trimethyl ene' ibis 2:methyl-.4ephenylthiazolium bromide) and-1G ce. oi'ethyl'alcohol, andthe reaction mii;- turewasziaeated eatr the refiuxingftempstature for ftffmmutes. .fitter ,chilling 19e 0. o., theeye-wes collected on a. filter and Washedl well with water. The yield of dye was 5 per cent after two reciystallizations from methyl alcohol. The reddish `emstals with vgreen '-reffex had a, "meting point of T6236@ C1 'with #decomposition fand" they sensitized a. photographic gelatino-silver-bromoiodide emulsion to about 610 me with maximum sensitivity at about 560 mit.

utes.

ethylene bis(2-methylbenzothiazolium p-toluenesulfonate), 10 cc. of ethyl alcohol and 0.20 g. of triethylamine, and the reaction mixture was heated at the reiluxing temperature for 20 min- The cool mixture was stirred with ether. After chilling at C., the ether layer was decanted. The residue was dissolved in hot methyl alcohol and treated with a hot 'solution of sodium iodide (3 g.) in methyl alcohol. After chilllng, the dye was collected on a llter and washed with methyl alcohol and then water. The yield of dye was 30 per cent crude and 6 per cent after three recrystallizations from methyl alcohol (300 c'c. per gram of dye). The blue crystals had a melting point of 127-128" C. with decomposition, and they sensitized a photographic gelatinosilver-bromoiodide emulsion to about 630 mp. with maximum sensitivity at about 600 mit and with a minium at about 500 mii.

The bis cyclammonium Quaternary salts represented by Formula. III above can be prepared by heating at least two molecular proportions of a heterocyclic nitrogen base containing in the aor fy-position an alkyl group selected from those having the following general formula:

wherein R2 represents a. hydrogen atom or an alkyl group, with Vone molecular proportion of an alkylene salt selected from those represented by the following general formula:

wherein D and X have the values set forth above. Typical alkylene salts are: ethylene dl-p-toluenesulfonate, trimethylene dibromide, propylene diiodide, decamethylene dibromide, hexamethylene dibromide, tetramethylene dichloride, w,wxylene dibromide, diethyl-a-ethane disulfate, methane disulfonic dimethyl ester, ethane disulfonic diethyl ester, 1,4-dibromocyclohexane, etc. The following examples will serve to illustrate further the preparation of bis cyclamrnonium Quaternary salts by this method.

Eample 13.-'-3,3'-ethylene bis (Z-methylbenzo- Y thiazolum-p-toluenesulfonate) 2.98 g. (2 mols.) of 2-methylbenzothlazole'and 3.7 g. (1 mol.) of ethylene di-p-toluenesulfonate were heated together in an oil bath at 105 to 115 C. for about 90 hours. After stirring the viscous mass with ether, the ethereal layer was decanted and the residue became crystalline as it was stirred with acetone. The yield of crystalline bis quaternary salt was 30 per cent. It melted at 152 to 155 C.

Example 14.--1,1' trimm/zeney msu-methylquinolinzum iodide) nary iodide collected on a filter.

14.9 g. (2 mois.) of amethymenzotniazole and 1,0.1f-g'. (1 mol.) of ,trimethylene bromide-were bij 14 heated together in a sealed tube at 9'1- to 10050.- for one week. The tube was opened and the liquid portion of the reaction mixture was decanted. The solid was twice recrystallized from methyll alcohol. The bis quaternary salt thus obtained in 31 per cent yield hada melting point of 257 t'o' 259 C. with decomposition.

Example 16.-3,3trimethylene bfis(2-mcthyl-4- phenylthiaeolium bromide) 1.7 g. and can be employed without further puri# fication.

The 3,3alkylene bis (thiazoliurn salts) can also be prepared by condensing a N,Nbis(thioacet-I yl)alkylenediamine with .a halogenated ketone selected from those represented by the following4 general formula:

Xz-CI-Iz--CO--Rs wherein X2 represents a chlorine, bromine or iodine atom and Rs represents a hydrocarbon radical, e. g, methyl, ethyl, phenyl, etc. The following examples will serve to illustrate further the manner of preparing bis -quaternary salts by this method. I

83g, (1 mol.) of N,N"-bis(thioacetyl)ethylenediamine and 25.64 g. (3 mols.) of phenacyl chloride were heated together in an oil bath at .QU-112 C. for 5 hours. The cooledreaction mixture was purified by washing with several (3 to 5) portions of acetone and then with ether.. The resulting bis quaternary salt was a tansolid (54 per cent yield).

The N,N-bis(thioacetyl)ethylenediamine employed above was prepared as follows: 23 g. (1 mol.) of N,N'bis(acetyl)-ethylenediamine (Hofmann, Ber. 21, 2332)and '75 cc, of pyridine were heated together at 100-120 C. (oil bath). To the hot mixture were added 37 g. of phosphorus pentasulde in small portions, with stirring, over a period of about minutes. A vg'orousre'action took place. After addition of the phosphorus pentasulfide, heating and stirring were continued for a further 10 minutes and then to the reaction mixture were added cc. of hot water. The thioacetyl compound separated upon chilling the reaction mixture and jwas collected on a Vfilter., washed 4with water and dried. It can be used withoutiurther purification.

. mamie fzsfremyzene bez-rezgzmemyztm! z'gg (lemok) of-:N,N"-bis (thioacetyllethyleneu diamine and .39:25 og. (2 -molsf ofachloroacetone wereplaced'togetherlinrza'ask tted with a long air'condenser and heatedx.iinaanaoil-.bathrat 901C. A vigorous reaction took place. The reaction i'lzrskwasu'emovedA from the-oil baithuntilthe reaction subsideelan`:l.-iwasl then' heated-1a; further 30 minutesfat-:Qtorlfsa -The cooled reaction-mixturepwasvtriturated with acetone, .collected onI a ltenand dried.. This forude bis Quaternary salt was-=extracted--withhot ethyl alcohol (350- cc.) to removef-lzvyfproclucts.y Theeresidue from `the extractionzwa's reerystallized--frommethyl alcohol, using .SNor-i-teA (activatedeharcoal) -`to decolorize thermethylalcohol solution. The bis Quaternary salt was fobtaned eas colorless crystals, melting about 300 C.

f-llheffbislalkylmeroapto cyclammonium quaternary .salts represented .by For-mula V above.' can bec-prepared (by heating tat -least two molecular proportienssosa heterocyclic .nitrogen base containing in the aor 'y-position analkylmercapto group, with one molecular proportion of an alkylene salt selected from those represented by the following formula:

.Example c9.-3,3'-memyzene bisqthiobenzothz'azolone) 112:35 1g.' .ofidilZebenzothiazolyhnercapto) methane :and :e1-crystal of iodine were heated together infan foiirloath-fat 1201)#220" C.\ for -two hours 'and 2024l fC. or one hour. The cool mixture was ,strredxwlth methyl `alcohol and theialcoholic laytemvazsecanted: `flheresidue wasstirredwith acetone, .lteredsand :washedethe `:product with acetone; 'Theuayieldt Lofintermediate was -51 iper cent crude and 41 pereeutatter-fonerecrystalliza-z 16' tionafromapyrldine (20 cc.:pergrampf-interm diate) The -tan -crystals Ihadx-a lmeltng.gpoint'ff 291-293 JTC. The' di (2benzotlnazolylmercapto)- methane: g

was prepared as fellows '813'35 rg. (-2 molsf) foffZ- mercaptobenzothiazole,4:35 g. (11; moll) of-methiviene-:bromi 2lev andfxasolution of 'B13-g. (.2 mols) of S5 Iper cent potassium Yhydroxide-in A50 c cn-of ethyl alcohol were y heated together at. the Areiiuxing temperature for -onelhour. After chilling overnight, the solid-was collected'fona ltergand- Washed with ethyl alcohol and;` then lwithvwater.` The yield'ofvintermediate was'lper-cent crude ended-percent after one recrystallization'rom methylalcohol (-50 cc. :pergramof .intermediate-)vf The almostcolorlesscrystals -had a lmeltingepoi-nt o 9e-91C. y,

Ihave also foundthatloisQuaternarysalts-rene` resented by Formula III above can be condensed with p-dalkylaminobenzaldehydes and p-dialkylaminocinnamaldehydes Vto give bis styryl type dyes. The condensations are advantageously carried out in the presenceofy as'ecorldaryfrnle having an ionizatio'n constant at"25'.\ C.-gre'ater than 11)5, e. g. piperid'i'ne; vk2--meth`yl1|iperidihc; etc. The following example will'srve to illustrate further the manner ofobtaining such bis dyes.

p-dimethylaminobenzaldehyde, AlO'cc. Vof fabsoliite' green reflex and frneltingat 281`C. with decent-Q position. Itsensitized a photographicsgeleltinoe' silver-loromiodide.` emulsion to about '630 frm .with maximum sensitivity iat 'about'595 4mjc..

In asimilar manner, p-f-diethylamihobenz'alde'- hyde, pdimethylaminocinnamaldehyde5pediethr ylaininocinnamaldehyde, etc. canbe condensed with 3;3'-e"thyl e`n"e bis' '(2'mthylilephenyltlhb'- llum chloride) or aiyoth'elils 'Quaternary salts These :new bis type yescbtelei 'it by the following general formula: v

r' -Z 'I Example 21.-Polymerz'c 3,3-trimethyleuethia.`

carhocyanine bromide N-Br ((ISHA 2.5 g. (2 mois.) 3,3'trimethy1ene bidz-methylbenzothiazolium bromide), 2.2 g.' '(6 mols.) oftriethylorthoformate and 20 cc. of acetic anhydride were refluxed for 20 minutes. #The mixture was then cooled and stirred, The dye was filtered off and washed on the filter rst with acetone, then with water and again with acetone.

The washed dye weighed 1.5 g. The dye was extracted with 300 cc. of methyl alcohol. The 300 "cci methyl Ualcoholic extract was concentrated to abouti 50 cc. The dye which separatedfrom the concentrated extract was ltered oi.l The dye Wasrecrystallized from'methyl alcohol (180 cc. per gram of dye) and obtained as dark green crystals, melting at 233-240 C. with decomposition." The dye sensitized a gelatino-silver-bromio- 59D my. In a similar' manner. 3,3 -trimethylene bis 2- methylbenzothiazoliuml bromide) .canA be condensed with triethyl orthoacetate, triethyl orthopropionate, triethyl orthobenzoate, triethyl 'o rthophenylacetate, etc. to give polymeric carbocyanine dide emulsion to -630 mp. with a maximum vat wherein D, n, R2, X and Z have the values given apoya; -R represents an; alkyl.- aralkylor aryl Acetic anhydride or ethyl alcohol can be f oxathiazolocarbocyanine iodide).

group, and Lm. represents a' positive integer, e. g.

Instead of employing. orthoesters, the bisv quaternary salts of Formula III can be condensed with diphenylformamidine to give polymeric carbocyanine dyes, with anilinoacrolein anil hydrochloride to give polymeric dicarbocyanine dyes and with glutaconic aldehydedianilide hydrochloride togive polymeric tricarbocyanine dyes. `Acidbinding agents, such as triethylamine, piperidine, are advantageously employed in these condensations. Y f

To preparejphotographic emulsionssensitized with my new dyes, it is only necessaryv to disperse the dyesy in -the emulsions. It is convenient to add the dyes to theemulsions from solutions in appropriate solvents. Methyl alcohol-has proven satisfactory for this purpose, Ethyl alcohol can also 1be used. sensitization by means of these dyes is, of course,directed primarily to the ordinarily employed gelatino-silver-halide developing-out emulsions. The dyes (one or more) are ordinarily incorporated Yin the washed, finished emulsions and should, of course, be uniformly distributed throughout the emulsion. The concentration of the dyes in the emulsions can vary widely, i. e; from about 5 to about 100 mg. per liter of flowable emulsion. The concentrationv of the dye will vary according to the type of light-sensitive material in the emulsion and according to the eiect desired. The suitable and most economical concentration for any given emulsion will be apparent to those skilled in the art of emulsion making. To prepare a gelatino-s'ilver-halide emulsion sensitized with one more of these dyes, the following procedure is satisfactory. A `quantity of the dye is dissolved in methyl alcohol or other suitable solvent, and a volume of this solution (which may be diluted with water) containing from 5 to :100 Ing. ofdye is. slowly added to 1000' cc. of. gelatino-silver-halide emulsion, with stirring. Stirring is continued until the dyeV is uniformly `distributed throughout the emulsion.

With most of 'these sensitizing dyes, 10to 20 mg. Y

corporated by other methods in photographic silver halide emulsions customarily employed in the art. For instance, the dyes may be incorporated by bathing a plate or llm upon whichan emulsion has been ycoated in a solution of the dye inl an appropriate solvent. V Bathing methods, however, are not to be'preferred ordinarily.

The accompanying drawing further illustrates my invention. Each ligure is a diagrammatic reproduction oia spectrogram showing'the' sensitivityofv a gelatino-silver-bromoiodide emulsion Vcontaining one Vof 'my newV N,N1alkylenecyam`ne sensitizing dyes, In Fig. 1, the curve depicts the sensitivity of an ordinary gelatino-silver-bromoiodide emulsion containing 3,3-ethylene bis(3- ethyl-4i-phenyloxathiazolgcarbocyanine iodide). In Fig, `2,` the. curve depicts the sensitivity of an ordinary; gelatino-silver-bromoiodide emulsion containing 3 ,3' -ethylene bis 3-et'hyl-4 -methyl- In Fig.'3,v the curve depicts the. sensitivity of an ordinary gelat- 4ino-silver-,bromoiodide emulsion containing 323- 'stai-,sse

My new dyes are of lower Solubility diffusibil'i-ty in photographie silver halide emulsions than many ofthe Vkooien sesitiing-dye's and are especially Valuable, therefore, in sensitiz'ing pho tographiceniulsions employed in color photo*- g'raphio element's- Whereb (relative) non-diiitsibility of the sensitizingy dyesy isredui-red'for goed Coloresepairation.A Irivson'ie Color processes, tile, sulj'stancesare pri-esent in the eimilsins that tend to dissolve the sensitizing dyes fromthe silver halde'grains; Low sluliility of these dyes minimizes this t'endny. Typical c9161". phot@- graphic processesand' typical color photographic elements comprising two "ormore differentially sensitized photograiihic silver halide emulsions are described in United StatesPatentv 2,113,329, datedApril 5,1938, in British Paten-ts 500,611 and 500,862 'eachv4 accepted. February 10, 1939, in United States Patent` 1,985,344, dted December 25, 1934, iti-United States' Patent1 .956,112, dted April l2; 1934 and n-.Uniteci States Patent 1,517,049, dated: l\loven`xber.` 25, 1924, for example. Another case where my new dyes are'especilly useful is in .the sensitization of variabley contrast materials suohias. described. in United States Pat-'- ent 234835528, dated? September 1.1,' 1945, United States Patent" 2,358,169,y dted September 1.2, 1944, and in United States-Patent' 2,358,06G1, dt.- led September'12, 1944i. Y

My new polymericdyes'are adso'roed Vim--iil`ie silver halide grain-s of the. photographic silver halide emulsions whenincorporated in thefem'uk sions;

Emulsions. sensitized.' with myfnew; dyes cert 5e coated. on the: usual supporte of paper; cellulose acetate film, glass, polyvinyl' ecetalf resin film, metal, etc. in theu'sualinamier-.a

What IV claim als my invention and.desiff te be secured byLetters Patent. ofitheUni-tedlstates is n i.y A photographie sil-verxhalide' emuls'i'oxfi` seri'- sitized with at. least'sorie4 sensiti'ziig biscarbocyanine dye selected Vfrom.those/Which i 'are' rege resented by the following: general. iermulaz- 2;, A. photographicV gelatinsilver-l'la-liie emule sion sensitized. with; at: least; onefsensitizing bis'.

Y 26' esrbceyaiiine eyeysietec" from those-winch are represented by lthe following gnralfdir'it'il.:"

wherein R represents a-pri'mary alkylgroup. of the formule4 CnHzn+i `whereinn represents aY p'o'sf itive integer of from. 1. to4, R represents einem berlselected. from the group.. consistingof' the methyl group and.. the phenylgroup, X represents anv anion, D represents. a member selected from the group yconsisting off the ethylene., the trimethylene and the tetramethylene groups, andZv represents the non-"metallic atomsrneoes'- sary to complete av heterooyoiic nucleus of the benzoxa-zole series.

3; A photographic gelatine-silver-bromoiodlde emulsion sensitized withal; least one sensitizing bis carbocyanine dye selected from those which 45 wherein Rg represents:y aw primary alkyl'- gromt.1 of the formula GaiHznilLwliereirr nrepreseritsarose itive. integer.,l of` fromv i to 4;, Rf' represents; tement-` .ber selected fromy the group?- consi'stingi of.- the methyl' group. and the phenyl. group; X repre- 50 sentsan anion, D represents 'at member selected fromk the' group consisting; of the= ethylene, the

trimethyleneand. theftetrametehylerie: groupg and Z; represents theV norremetallicatoms neeessry terl complete aheterocyclie. nucleusofithe benzwe azoleseries.V

4. A photographic gelatino-silver-bromoedide emulsion sensitized with the. bis carbocyanine; dye which representedby' metrici-lowing formule:-

21 22 emulsion sensitized with the bis carbocyanine dye REFERENCES CITED which is represented by the following formula:

o s The following references are ofV record in the \OH le of this patent:

UNITED STATES PATENTS o-oH=CH-CH=C L 5 CH3 N N/ Number Name Date 1,969,445 Brooker Aug. 7, 1934 02H5 I H2 2,075,153 Wilmanns Mar. 30, 1937 CH, 10 2,166,736 White et al July 18, 1939 o I 2,170,804 Brooker Aug. 29, 1939 \O 2,245,772 Wilson Aug. 19, 1947 CH2 2,245,773 Wilson Aug. 19, 1947 /CCHCH-CHJ H 2,278,947 Riester Apr. '1, 1942 \N S/ 15 2,282,115 Brooker et a1 May 5, 1942 Ck\1 OTHER REFERENCES 6 A photographic gelatin() Svebbromoiodide Chemical Abstracts 19:530; abstract of Proc.

emulsion sensitized with the bis carbocyanine dye ROY- S0 (LOIldOn) 96 B- 317-333 (1924). which is represented by the following formula: Chemical lAbstracts 16:3101; abstract of Brit.

Ha l LESLIE G. s. BRooKER. 35 

